Justin Beckerman, 18, built his own submarine out of a drainage pipe and other materials. The Navy hasn't recruited him yet, but he's open to a sales pitch. (Photos courtesy of Ken Beckerman)

THE NAUTILUS

Specs for Justin Beckerman’s homemade submarine: Cost: $2,000 (Dad paid for half). Building supplies included: 9 feet of plastic drainage pipe; three RV water tanks for ballast; wood; acrylic plastic; four batteries; 2,000 feet of wiring. Bells and whistles: A buoy with tether, emergency air supply, siren, strobe light. How long it took to build: Less than five months. Estimated max depth: 30 feet (It’s only been tested to 13 feet). Max speed: 1.3 knots Learn more: Read about the Nautilus and Justin’s other inventions at www.justinbeckerman.com.

You might call Justin Beckerman a backyard bubblehead.

But he’s definitely not a bubble brain. The high school junior from New Jersey used his smarts to build his own submarine — a one-man, lake-prowling monster capable of reaching depths of 30 feet.

Justin’s invention has made him a media darling in recent weeks, with appearances on CNN, Huffington Post, Fox affiliate stations and ABC News.

It’s not his first attempt at making a submarine, but it’s certainly his most successful — a previous iteration was made of plastic and duct tape and could dive a measly 2 feet.

“I’ve always been creating things,” explained Justin, who has built numerous remote-control vehicles and go-carts. “Sometimes, if I don’t make something the way I want it, I come back to it eventually.”

Hence his latest invention: the Nautilus.

He named the vessel in honor of the Navy’s first nuclear-powered sub. Only later did Justin, 18, learn it’s also the name of the submarine from Jules Verne’s “Twenty Thousand Leagues Under the Sea.”

Justin’s Nemo-esque voyages have taken him to the depths of Lake Hopatcong — about an hour’s drive from New York City — but they haven’t yielded any sea monsters. He has, however, seen the side of the dock, rocks and seaweed.

“I tried to attract fish by putting bread in the water, but I think the fish were too scared of the submarine,” he said.

Justin hopes to eventually get paid for his efforts — as an engineer. While he hasn’t had any Navy recruiters drop by his lab, he said he’d be open to hearing a sales pitch.

“I would certainly listen to them and see what they wanted to do,” said Justin, whose ambitions also include robots and airplanes.